Köroğlu, an art historian and archaeologist at Turkey’s Mimar Sinan University of Fine Arts, said the team suspects that the chest served as a symbolic coffin for the relics of a holy person — and that the fragments within it were associated with Jesus’ crucifixion.

She showed reporters at the site a stone with crosses carved into it. “This stone chest is very important to us. It has a history and is the most important artifact we have unearthed so far,” she said. The chest has been taken to a laboratory for further examination.

Köroğlu said her team has been working since 2009 at the church — which was built in the year 660, during the Byzantine era. She said the ruins of an ancient Roman bath were also found at the site, along with more than 1,000 human skeletons.